稠密气固两相流动的颗粒二阶矩方法及鼓泡床流化特性的模拟

Second-order moments of particles for dense gas-solid flow and numerical flow behavior simulation in bubbling fluidized bed

A second-order moment model of particles in dense gas-solid flow is proposed based on the kinetic theory of granular flow.The solid phase constitutive model is closed with the approximated third-order moment enclosure equation of particle velocity from the elementary transport theory.The boundary conditions of particles are proposed in considering the energy transfer and dissipations by collisions between the wall and particles.Flow behavior of particles is numerically simulated in a bubble fluidized bed,which indicates the distinct anisotropy behavior of the turbulent particles.Simulated particle velocities are in agreement with the measurements by Muller et al(2008) and Yuu et al(2001).Predicted second-order moment of velocity has the same trend as that of measurements.The calculated Reynolds stresses per unit bulk density agree with the measured data by Muller et al(2008) and with the fluctuating velocity of particles measured by Yuu et al(2001).